Scientists Giovanni de Micheli and Sandro Carrara at the École Polytechnique Fédérale de Lausanne in Switzerland have developed a tiny, portable personal laboratory: a 14mm-wide chip containing five sensors, a radio transmitter and a power delivery system, implanted just under the skin. The prototype chip provides an immediate analysis of chemicals in the blood, such as glucose and lactate, and the results are transmitted over the mobile-phone network to a doctor. The hope is that it will lead to more personalised care. MV